President Donald Trump’s relatively subdued Oval Office speech on border security included one particularly combative note: a challenge to the suggestion by Speaker of the House Nancy Pelosi that Trump’s proposed wall on the border with Mexico was immoral.

“Some have suggested a barrier is immoral,” the president said. “Then why do wealthy politicians build walls, fences and gates around their homes? They don’t build walls because they hate the people on the outside, but because they love the people on the inside. The only thing that is immoral is the politicians to do nothing and continue to allow more innocent people to be so horribly victimized.”

Even though Trump didn’t mention Pelosi by name, it seemed obvious that he was referring to her. Last week she said that “a wall is an immorality between countries,” adding: “It’s an old way of thinking. It isn’t cost-effective.” This isn’t a new position for her. In a “Meet the Press” interview in April 2017, she said: “The wall is, in my view, immoral, expensive, unwise.”

Even if it would have required some extemporizing, you might have thought Pelosi would have responded to Trump’s point about the morality of the wall when she and Senate Minority Leader Chuck Schumer delivered their televised response to the president.

But Pelosi didn’t engage on that issue, focusing on the importance of reopening the government, alternative ways to secure the border and the fact that women and children seeking to enter the United States are not a security threat, but a humanitarian challenge. She called the wall expensive and ineffective, but not immoral. Schumer seconded her on “ineffective” and added “unnecessary.”

There’s a huge difference in messaging between calling a wall ineffective or unnecessary and calling it immoral. The moral claim is associated with the view that most if not all would-be migrants should be welcomed to the United States and that claims for asylum should be assessed generously. It’s a view popular on the activist left of the Democratic Party but harder to sell to more moderate voters.

It also reflects a religious view of immigration. After Trump’s speech, Catholics opposed to the wall launched a Twitterstorm with the hashtag CatholicsOpposeTheWall. It was clear that most of their objections were moral and religious, not pragmatic, and extended far beyond the issue of the wall. One quoted the Gospel of Matthew: “I was a stranger and you did not invite me in, I needed clothes and you did not clothe me, I was sick and in prison and you did not look after me.”

In fact, the U.S. Catholic bishops, while paying lip service to border security, long have espoused what is close to an open borders policy. But it’s one thing for clerics to view the wall and immigration policy broadly through the lens of the Gospel’s injunctions about welcoming the stranger. For the Democratic Party to take that view is another matter.

Many voters, even if they oppose Trump’s wall and other policies such as the separation of families at the border, still are uneasy about illegal immigration. Is that why Pelsoi and Schumer didn’t harp on the “immorality” of the wall in their remarks?

A proposal to take seriously: A $25 billion border security endowment, in exchange for securing the position of all those in the country without permission, except the sliver involved in violence and crime.